Previous machines are known for preparing and applying clips onto the neck of a plastic bag. For example, U.S. Pat. Nos. 3,163,969 and 3,163,972 disclose methods and apparatus for applying bag closures, or clips, onto the open neck portion of a plastic bag inside of which articles have previously been inserted. In the process of designing thermoforming lines and bagging machines for thermoformed articles, it has been realized that improvements are now needed in the design of bag closing machines in order to more accurately, quickly, and repeatedly apply clips onto plastic bags that contain articles.
More particularly, present bag closing machines oftentimes do not properly or completely apply a clip onto an open neck portion of a polyethylene plastic bag. As the operating speeds of thermoforming machines and bagging machines have increased, this problem has been exacerbated as the increased speeds frequently lead to an increase in misapplied clips to bags.
Accordingly, improvements are needed in the manner in which an open neck of a plastic bag is delivered, presented and prepared for delivery into a bag closing machine, where a clip is applied onto the open neck portion of the bag to close the bag.